The present invention relates to a flexible processing system.
Advances in computer technology have provided high performance, miniaturized computers that are inexpensive. Even with these impressive achievements, manufacturers are constantly looking for improvements in areas such as user-friendliness and connectivity so that users can be productive any time anywhere. Wireless communications networks offer the user such capabilities. However, the speed and computational robustness of present-day wireless communications systems leave much to be desired.
In response, the industry is adopting new technologies such as 802.11A, GPRS and EDGE wireless networking technologies that drive transparent connections between all computing, communications, audio and video devices. 802.11A transceivers communicate at the 5 GHz frequency and offer 100 Mbps throughput, in contrast to the 2.4 GHz frequency and the 11 Mbps throughput of 802.11B transceivers.
General Packet Radio Service (GPRS) brings packet data connectivity to the Global System for Mobile Communications (GSM) market. GPRS integrates GSM and Internet Protocol (IP) technologies and is a bearer for different types of wireless data applications with bursty data, especially WAP-based information retrieval and database access. GPRS packet-switched data technology makes efficient use of radio and network resources. Session set-up is nearly instantaneous, while higher bit rates enable convenient personal and business applications. Consequently, GPRS not only makes wireless applications more usable, but also opens up a variety of new applications in personal messaging and wireless corporate intranet access.
EDGE stands for Enhanced Data rates for Global Evolution. EDGE is the result of a joint effort between TDMA operators, vendors and carriers and the GSM Alliance to develop a common set of third generation wireless standards that support high-speed modulation. EDGE is a major component in the UWC-136 standard that TDMA carriers have proposed as their third-generation standard of choice. Using existing infrastructure, EDGE technology enables data transmission speeds of up to 384 kilobits per second.
The new standards such as 802.11A, EDGE and GPRS achieve increased transmission throughput by using complex digital signal processing algorithms, many of which require high processing power exceeding that offered by today's baseband processors.
One way to increase processing power is to perform computations in parallel using hardwired, dedicated processors that are optimized for one particular radio frequency (RF) protocol. Although highly effective when geared to handle one RF protocol, this approach is relatively inflexible and cannot be easily switched to handle today's multi-mode cellular telephones that need to communicate with a plurality of RF protocols.
Another way to increase processing power is to perform computations in parallel using general-purpose processors. Although flexible in programmability, such an approach may not provide the highest possible computational power that may be needed when performing digital signal processing for specific wireless applications such as 802.11A or GPRS applications.
Yet another approach uses reconfigurable logic computer architectures that include an array of programmable logic and programmable interconnect elements. The elements can be configured and reconfigured by the end user to implement a wide range of logic functions and digital circuits and to implement custom algorithm-specific circuits that accelerate the execution of the algorithm. High levels of performance are achieved because the gate-level customizations made possible with FPGAs results in an extremely efficient circuit organization that uses customized data-paths and “hardwired” control structures. These circuits exhibit significant fine-grained, gate-level parallelism that is not achievable with programmable, instruction-based technologies such as microprocessors or supercomputers. This makes such architectures especially well suited to applications requiring the execution of multiple computations during the processing of a large amount of data. A basic reconfigurable system consists of two elements: a reconfigurable circuit resource of sufficient size and complexity, and a library of circuit descriptions (configurations) that can be down-loaded into the resource to configure it. The reconfigurable resource would consist of a uniform array of orthogonal logic elements (general-purpose elements with no fixed functionality) that would be capable of being configured to implement any desired digital function. The configuration library would contain the basic logic and interconnect primitives that could be used to create larger and more complex circuit descriptions. The circuit descriptions in the library could also include more complex structures such as counters, multiplexers, small memories, and even structures such as controllers, large memories and microcontroller cores. For example, U.S. Pat. No. 5,784,636 to Rupp on Jul. 21, 1998 discusses a reconfigurable processor architecture using a programmable logic structure called an Adaptive Logic Processor (ALP). The Rupp structure is similar to an extendible field programmable gate array (FPGA) and is optimized for the implementation of program specific pipeline functions, where the function may be changed any number of times during the progress of a computation. A Reconfigurable Pipeline Instruction Control (RPIC) unit is used for loading the pipeline functions into the ALP during the configuration process and coordinating the operations of the ALP with other information processing structures, such as memory, I/O devices, and arithmetic processing units. Multiple components having the Rupp reconfigurable architecture may be combined to produce high performance parallel processing systems based on the Single Instruction Multiple Data (SIMD) architecture concept.